12.7 cylinder head bolt difference

I have rebuilt few s60 always used PDI without issues but this time I went with KMP bolts and to my surprise there is a difference.

PDI is 10.9 vs KMP 12.9 and u can see the difference in thickness. Just for anyone maybe looking for stronger bolts these seem to be a good option.

 

That looks rough these bolts I bought got higher tensile strength then PAI 1000mpa vs 1200mpa this was accidental find I thought they were all the same.

If you need them let me know I got them for 165$ plus taxes

Looking at charts online it appropriately 25% stronger then oem

 

Yes after 2002 they call for 220lbs before 2002 it's between 185lbs to 210lbs . But I am curious if torquing to 220 on older engines have any benefits or drawbacks mine is bk 2002 . I would assume it would provide a little better sealing. Last time I had head off do to a broken rocker arm I torqued it to 200lbs never had an issue on a 600hp tune been like that for 4 years until now. I am debating weather to stick to 210 limit vs 220 not sure yet would like to hear some opinion on it. I think higher tensile bolts would provide a better resistance to head lifting if you are in to tuning. since I got everything off I went ahead changed my 7650 tips with 7014 will see how she behaves

 

That's interesting I will check the gasket I ordered but one thing that came in different was exhaust manifold gaskets. Usually they are just thin steel but this time they are steel with graphite on both sides much thicker like the head gasket. Seems to me there were some upgrading going on in past few years? Give me few mins I will take a pic of the exhaust seals

New one vs old one I have always worked with old style and new one in my opinion are much better should provide a better seal less chance of leaks.

Only thing Detroit kits are missing now are thicker turbo mounting gasket that cat uses